1. Field of the Invention
The present invention relates to pipe coupling members suitable for handling high-pressure fluids such as gaseous hydrogen. More particularly, the present invention relates to a female coupling member and a male coupling member.
2. Description of the Related Art
Recently, fuel cell vehicles equipped with a fuel cell using gaseous hydrogen as a power source have been put to practical use. Such fuel cell vehicles need to be supplied with gaseous hydrogen at a gaseous hydrogen supply station similar to a filling station for gasoline engine vehicles, which are the mainstream at present. In this case, a female pipe coupling member attached to an outlet of a hose for supplying gaseous hydrogen discharged from a gaseous hydrogen storage tank at the station is connected to a male pipe coupling member attached to an inlet of a gaseous hydrogen storage tank on the vehicle to supply gaseous hydrogen to the vehicle.
The gaseous hydrogen in this case has usually been pressurized to about 70 MPa. Therefore, it is necessary to take all possible measures to avoid occurrence of accident when the male and female pipe coupling members are connected together. For example, it is necessary that the supply of gaseous hydrogen should be started after the male and female pipe coupling members have been connected together completely, and it is necessary to prevent the pipe coupling members from being accidentally disconnected from each other after the supply of gaseous hydrogen has been started. In addition, it is necessary to make certain that there is no gaseous hydrogen pressure in the pipe coupling members when they are to be connected and disconnected.
However, there have not been developed pipe couplings meeting the above-described demands.
Patent Literature 1 discloses a pipe coupling suitable for high-pressure fluids. Patent Literature 1: Japanese Patent No. 3894578.
The pipe coupling of Patent Literature 1, however, cannot sufficiently satisfy the above-described demands that need to be met in order to safely handle high-pressure fluids such as gaseous hydrogen. For example, even during the supply of fluid, if an on-off valve-actuating lever of the pipe coupling is pivoted, a sleeve returns, which allows the pipe coupling to be disconnected. Further, in Patent Literature 1, the valve-actuating lever needs to be pivoted after the male member has been inserted into the female member, although the title of the invention is “Rapid Coupling”; therefore, more time and effort are needed for the connecting operation than in the case of pipe couplings in which connection of the male and female members is completed simply by inserting the male member into the female member.